* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
  transition: all 0.25s;
}
li {
  list-style: none;
}
.header .banner {
  position: relative;
  width: 100%;
  height: 760px;
  overflow: hidden;
}
/* 宽度>1130px的nav */
/* 自适应页面，宽度默认占95%，大于1200px的时候就保持1200px */
/* 再用绝对定位 + transform实现居中 */
.nav, .nav-w {
  position: fixed;
  z-index: 9999;
  width: 100%;
  height: 64.64px;
  transition: all .25s;
}
.nav {
  top: 0;
}
.nav-w {
  top: 0;
  background-color: #fff; 
}
.nav .sub-nav, .nav-w .sub-nav {
  position: absolute;
  width: 500%;
  left: 50%;
  transform: translate(-50%, 0);
  height: auto;
  padding-top: 10px;
  visibility: hidden;
  opacity: 0;
  text-align: center;
  transition: all .25s;
}
.nav .nav-main, .nav-w .nav-main {
  display: inline-block;
  padding: 20px 0;
}
.nav-content {
  display: flex;
  justify-content: space-between;
  align-items: center;
  position: absolute;
  left: 50%;
  z-index: 9999;
  padding-top: 0;
  width: 100%;
  max-width: 1300px;
  transform: translate(-50%, 0);
  padding: 0 2.5%;
}
.nav .sub-nav {
  display: none;
}
.nav-w .sub-nav {
  display: block;
}
.nav-main > li > a {
  position: relative;
}
.nav-main > li > a::after {
  content: '';
  position: absolute;
  left: 50%;
  bottom: -5px;
  width: 0;
  height: 3px;
  background-color: rgb(0,82,217);
  transition: all 0.25s;
}
.nav-main > li:hover > a::after {
  left: 0;
  width: 100%;
}
.nav-main > li.language > a::after {
  display: none;
}
.nav-w .sub-nav.active {
  padding-top: 20px;
  visibility: visible;
  opacity: 1;
}
.nav-w .sub-nav li {
  display: block;
  padding: 10px 0;
}
.nav img, .nav-w img {
  width: 180px;
  padding: 20px 0;
}
.nav li, .nav-w li {
  position: relative;
  display: inline-block;
  margin: 0 25px;
}
.nav li a, .nav-w li a {
  text-decoration: none;
  font-weight: 600;
  color: #fff;
}
.nav-w li a {
  color: rgb(54,57,57);
}
.nav .sub-nav li a, .nav-w .sub-nav li a {
  margin: 0;
  font-weight: 400;
  color:rgb(130, 130, 130)
}
.nav-w .sub-nav li a:hover {
  color: #000;
}
.nav li.language a, .nav-w li.language a {
  margin: 0 5px;
  font-weight: 400;
  transition: all 0.25s;
}
.nav li.language a {
  color: rgb(205, 205, 205)
}
.nav li.language a.active, .nav li.language a:hover {
  color: #fff;
}
.nav-w li.language a {
  color: rgb(90, 90, 90);
}
.nav-w li.language a.active, .nav-w li.language a:hover {
  color: #000;
}
.header .banner-group {
  position: absolute;
  width: 300%;
  height: 100%;
}
.header .banner-group li{
  position: relative;
  float: left;
  overflow: hidden;
  width: calc(100% / 3);
  height: 100%;
}
.header .banner-group img.background {
  position: absolute;
  left: 50%;
  top:50%;
  transform: translate(-50%, -50%);
  width: 100%;
  height: 100%;
  object-fit:cover;
  filter: brightness(0.45);
}
.header .banner-group .text {
  position: absolute;
  left: 50%;
  top: 30%;
  transform: translate(-50%,0);
  width: 100%;
  max-width:1300px;
  padding: 0 2.5%;
  font-weight: 400;
  color: #fff;
}
.header .banner-group .text h1, .header .banner-group .text p {
  width: 60%;
}
.header .banner-group .text h1 {
  padding: 20px 0;
  margin-left: 40px;
  opacity: 0;
  font-size: 48px;
  font-weight: 400;
  transition-delay: 0.25s;
}
.header .banner-group .text.active h1 {
  opacity: 1;
  margin-left: 0;
}
.header .banner-group .text p {
  margin-left: 40px;
  opacity: 0;
  font-size: 18px;
  line-height: 30px;
  transition-delay: 0.5s;
}
.header .banner-group .text.active p {
  opacity: 1;
  margin-left: 0;
}
.resp-banner {
  position: relative;
  display: flex;
  width: 100%;
  max-width: 1300px;
  transform: translate(-50%,0);
  margin: 40px 0 40px 50%;
  padding: 20px 2.5%;
}
.resp-banner .banner {
  position: relative;
  width: 42.5vw;
  height: 42.5vw;
  overflow: hidden;
}
.resp-banner .banner:hover .page-switcher {
  opacity: 1;
}
/* 构造长宽相同的盒子 */
/* .resp-banner .banner::before{
  content: "";
  padding-top: 100%;
  display: block;
} */
.resp-banner .page-switcher {
  position: absolute;
  z-index: 9999;
  right: 0;
  bottom: 0;
  padding: 15px 8%;
  opacity: 0;
  font-size: 28px;
  font-weight: 300;
  color: rgb(255,255,255,.7);
}
.page-switcher > span {
  padding: 8px;
  cursor: pointer;
}
.resp-banner .banner > img {
  position: absolute;
  top: 0;
  right: 0;
  z-index: 9999;
  height: 100%;
}
.resp-banner > .text {
  margin: auto;
  top: 50%;
  width: 50%;
  padding: 0 50px;
  cursor: pointer;
}
.resp-banner > .text:hover h2 {
  color: rgb(0,82,217);
}
.resp-banner > .text h2{
  font-size: 32px;
  font-weight: 600;
}
.resp-banner > .text p {
  padding: 20px 0;
  font-size: 18px;
}
.resp-banner > .text img {
  margin-top: -15px;
}
.resp-banner .banner-content {
  position: absolute;
  width: 100%;
  height: 100%;
  top: 0;
  object-fit: cover;
  opacity: 0;
  transition: all .25s;
}
.resp-banner .banner-content::after {
  content: '';
  position: absolute;
  z-index: 50;
  width: 100%;
  height: 100%;
  background-image: linear-gradient(0deg, rgb(0,0,0,.5), transparent);
}
.resp-banner .banner-content img {
  position: absolute;
  top:0;
  height: 100%;
}
.resp-banner .banner .text {
  position: absolute;   
  bottom: 0;
  z-index: 90;
  width: 90%;
  padding: 50px 30px;
  color: #fff;
}
.resp-banner .banner .text h4 {
  font-size: 24px;
  padding: 15px 0;
}
.dev-banner {
  position: relative;
  width: 100%;
}
.dev-banner > .text {
  position: absolute;   
  top: 10vw;
  padding: 20px 6vw;
  z-index: 999;
  width: calc(100% - 12vw);
  cursor: pointer;
}
.dev-banner > .text:hover h2 {
  color: rgb(0,82,217);
}
.dev-banner > .text h2{
  font-size: 48px;
  font-weight: 600;
}
.dev-banner > .text p {
  padding: 20px 0;
  font-size: 18px;
}
.dev-banner > .text img {
  margin-top: -15px;
}
.dev-banner .banner-group {
  position: relative;
  width: 100%;
}
.dev-banner .banner-group li {
  opacity: 0;
  position: absolute;
  transition: all .25s;
}
.dev-banner .banner-group li.active {
  opacity: 1;
}
.dev-banner .banner-group img {
  width: 100%;
  object-fit: cover;
}
.dev-banner .operation-bar {
  position: absolute;
  top: 43vw;
  left: 6vw;
  z-index: 999;
  display: flex;
  justify-content: space-between;
  width: calc(100% - 12vw);
  padding: 40px 0;
}
.dev-banner .direction {
  display: flex;
  justify-content: space-between;
  width: 150px;
}
.dev-banner .operation-bar img {
  width: 60px;
  cursor: pointer;
}
.dev-banner .operation-bar img.arrow-left {
  transform: rotate(180deg);
}
.dev-banner .operation-bar ul {
  display: flex;
  justify-content: space-between;
  width: 70px;
}